Magnesium Compound Containing Patents (Class 501/108)
  • Publication number: 20040131884
    Abstract: It is an object of the present invention to provide a polycrystalline MgO deposition material which is capable of obtaining a good discharge response characteristic over a wide temperature range. Additionally, it is another object of the present invention to provide a plasma display panel with an improved luminance and a material for the plasma display panel which can remarkably reduce the number of address ICs without lowering the panel luminance. In order to achieve the objects, there is provided an improvement of a polycrystalline MgO deposition material for a passivation layer of the plasma display panel. A characteristic structure is that the polycrystalline MgO deposition material is formed of a sintered pellet of polycrystalline MgO, of which MgO purity is more than 99.9% and relative density is more than 90%. Further, a Si concentration in the polycrystalline MgO is more than 30 ppm and less than 500 ppm.
    Type: Application
    Filed: October 10, 2003
    Publication date: July 8, 2004
    Inventors: Eung Chul Park, Hideaki Sakurai, Yoshirou Kuromitsu, Ginjiro Toyoguchi
  • Patent number: 6723442
    Abstract: Disclosed is a ceramic material which is suitable for coating a body by way of a thermal spraying method and which has a coefficient of longitudinal thermal expansion that may be matched to that of a metal. The ceramic material includes 10 to 95% by weight of MgAl2O4, 5 to 90% by weight of MgO, up to 20% by weight of Al2O3, remainder standard impurities, and has grains of MgO which are embedded in a matrix of MgAl2O4.
    Type: Grant
    Filed: April 9, 2002
    Date of Patent: April 20, 2004
    Assignee: Siemens Aktiengesellschaft
    Inventors: Jens Decker, Thomas Jansing, Günter Schürholt
  • Patent number: 6713417
    Abstract: An insulative ceramic compact is composed of a fired mixture of (A) a MgAl2O4, Mg3B2O6 and/or Mg2B205 ceramic powder, and (B) a glass powder including from about 13 to 50% by weight of silicon oxide in terms of SiO2, from 8 to 60% by weight of boron oxide in terms of B2O3, about 20% by weight or less of aluminum oxide in terms of Al2O3, and from about 10 to 55% by weight of magnesium oxide in terms of MgO. The insulative ceramic compact can be obtained by firing at low temperatures of about 1000° C. or less, can be obtained by sintering with Ag or Cu, has a low dielectric constant and a high Q value, and is suitable for use in the high-frequency range.
    Type: Grant
    Filed: July 19, 2001
    Date of Patent: March 30, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Osamu Chikagawa, Naoya Mori, Yasutaka Sugimoto
  • Patent number: 6689202
    Abstract: Blocks of material are prepared in a variety of shapes and sizes to be used in the fabrication of models for dental restorations. The material comprises a partially sintered ceramic material. The blocks are used to manufacture molds using CAD/CAM methods and equipment. The molds are useful in the manufacture of dental restorations using ceramics, metals, alloys, or powders thereof, and composite materials. The models milled from the blanks may be used to manufacture a variety of dental restorations including, but not limited to, crowns, bridges, space maintainers, tooth replacement appliances, orthodontic retainers, dentures, posts, jackets, inlays, onlays, facings, veneers, facets, implants, abutments, splints, partial crowns, teeth, cylinders, pins, and connectors.
    Type: Grant
    Filed: July 13, 2001
    Date of Patent: February 10, 2004
    Assignee: Jeneric/Pentron Incorporated
    Inventor: Carlino Panzera
  • Patent number: 6605316
    Abstract: Provided are low-cost, mechanically strong, highly electronically conductive porous substrates and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures. The invention provides solid state electrochemical device substrates of novel composition and techniques for forming thin electrode/membrane/electrolyte coatings on the novel or more conventional substrates. In particular, in one embodiment the invention provides techniques for co-firing of device substrate (often an electrode) with an electrolyte or membrane layer to form densified electrolyte/membrane films 5 to 20 microns thick. In another embodiment, densified electrolyte/membrane films 5 to 20 microns thick may be formed on a pre-sintered substrate by a constrained sintering process. In some cases, the substrate may be a porous metal, alloy, or non-nickel cermet incorporating one or more of the transition metals Cr, Fe, Cu and Ag, or alloys thereof.
    Type: Grant
    Filed: July 27, 2000
    Date of Patent: August 12, 2003
    Assignee: The Regents of the University of California
    Inventors: Steven J. Visco, Craig P. Jacobson, Lutgard C. DeJonghe
  • Patent number: 6602623
    Abstract: A low-temperature firing ceramic composition contains Sr2MgSi2O7 crystals forming a major crystal phase of the composition. This composition can be produced, for example, by a process including the steps of (a) mixing together a silica powder, a magnesia powder and a strontium oxide powder to obtain a powder mixture; (b) subjecting the powder mixture to a calcination at a temperature of 1,000-1,200° C. to obtain a calcination product containing Sr2MgSi2O7 crystals; (c) mixing the calcination product with alumina powder, boron oxide powder, lithium oxide powder, binder and ethanol to obtain a powder mixture; (d) granulating the powder mixture; (e) shaping the resulting granules into a green body; (f) compacting the green body by a hydrostatic pressing (CIP); and (g) firing the resulting compact in an atmosphere of air, thereby obtaining the composition.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: August 5, 2003
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Hidetoshi Mizutani, Tsutomu Sakai, Masashi Suzumura, Satoshi Iio
  • Publication number: 20030109373
    Abstract: The invention relates to a batch composition for producing a refractory ceramic shaped body, to a shaped body produced therefrom and to the use thereof. The components used are: 68 to 97 wt.- % molten magnesite, sintered magnesite or mixtures thereof, 3 to 20 wt.- % CaO and 0 to 25 wt.- % of a third component.
    Type: Application
    Filed: October 15, 2002
    Publication date: June 12, 2003
    Inventors: Gerald Buchebner, Harald Harmuth, Thomas Molinari
  • Patent number: 6541409
    Abstract: An economical and environment-friendly processes for the synthesis of anionic clays and the products made therefrom. It involves reacting a slurry comprising non-peptized boehmite with a magnesium source. There is no necessity to wash or filter the product. It can be spray dried directly to form microspheres or can be extruded to form shaped bodies. The product can be combined with other ingredients in the manufacture of catalysts, absorbents, pharmaceuticals, cosmetics, detergents, and other commodity products that contain anionic clays.
    Type: Grant
    Filed: January 26, 2000
    Date of Patent: April 1, 2003
    Assignee: Akzo Nobel N.V.
    Inventors: William Jones, Dennis Stamires, Michael Brady
  • Patent number: 6534430
    Abstract: A sensor material for measuring physical parameters capable of configuring a sensor capable of directly measuring a high value of physical parameters such as high stress or high pressure without employing a pressure resistance container. The sensor material for measuring static and dynamic physical parameters includes a matrix made of an electrically insulating ceramic material, and piezoresistance materials which are dispersed in the matrix so as to be electrically continuous to each other.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: March 18, 2003
    Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho
    Inventors: Hiroaki Makino, Mitsuru Asai, Nobuo Kamiya, Shin Tajima, Katsunori Yamada, Hiroshi Hohjo
  • Patent number: 6534161
    Abstract: A crystallized glass composition contains a principal ingredient comprising SiO2, MgO and Al2O3 and contains about 2 to 20 parts by weight of B2O3 relative to 100 parts by weight of the principal ingredient. In a ternary diagram, the weight ratio (SiO2, MgO, Al2O3) lies within a region surrounded by point A (44.0, 55.0, 1.0), point B (34.5, 64.5, 1.0), point C (35.0, 30.0, 35.0) and point D (44.5, 30.0, 25.5).
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: March 18, 2003
    Assignee: Murata Manufacturing Co. Ltd
    Inventors: Hiromichi Kawakami, Toshiki Tanaka, Shizuharu Watanabe, Hiroshi Takagi
  • Patent number: 6514892
    Abstract: Transparent solid, fused microspheres are provided. In one embodiment, the microspheres contain alumina, zirconia, and silica in a total content of at least about 70% by weight, based on the total weight of the solid, fused microspheres, wherein the total content of alumina and zirconia is greater than the content of silica, and further wherein the microspheres have an index of refraction of at least about 1.6 and are useful as lens elements.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: February 4, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Toshihiro Kasai, Kenton D. Budd, Stephen L. Lieder, James A. Laird, Chikafumi Yokoyama, Toshinori Naruse, Kenji Matsumoto, Hirohiko Ono
  • Publication number: 20020165081
    Abstract: Ceramic mass transfer media suitable for use in thermal regenerative oxidizers made using a mixture of a clay, talc and optionally a dolomitic limestone have enhanced resistance to environments containing halogens and hydrogen halides.
    Type: Application
    Filed: May 4, 2001
    Publication date: November 7, 2002
    Inventors: John S. Reid, Thomas Szymanski, Karen C. Beal
  • Patent number: 6461991
    Abstract: A re-usable alumina-magnesia graphite refractory suitably used for a refractory for continuous casting, such as a long nozzle used for pouring a molten metal from a ladle capable of re-use or intermittent use to a tundish, an immersion nozzle used for charging a molten metal from a tundish to a mold and a long stopper for controlling the flow rate of the molten steel; and produced by blending 3 to 60 wt % of magnesia having a particle size of 0.02 to 1.0 mm to a compound comprising mainly alumina and graphite, and kneading, molding, and baking the compound. The raw material compound comprising mainly alumina and graphite can contain spinel or zirconia.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: October 8, 2002
    Assignee: Krosaki Corporation
    Inventors: Koji Ogata, Shoji Iitsuka
  • Patent number: 6458732
    Abstract: A dry refractory composition having superior insulating value. The dry refractory composition also may have excellent resistance to molten metals and slags. The composition includes filler lightweight material, which may be selected from perlite, vermiculite, expanded shale, expanded fireclay, expanded alumina silica hollow spheres, bubble alumina, sintered porous alumina, alumina spinel insulating aggregate, calcium alumina insulating aggregate, expanded mulllite, cordierite, and anorthite, and matrix material, which may be selected from calcined alumina, fused alumina, sintered magnesia, fused magnesia, silica fume, fused silica, silicon carbide, boron carbide, titanium diboride, zirconium boride, boron nitride, aluminum nitride, silicon nitride, Sialon, titanium oxide, barium sulfate, zircon, a sillimanite group mineral, pyrophyllite, fireclay, carbon, and calcium fluoride.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: October 1, 2002
    Assignee: Allied Mineral Products, Inc.
    Inventors: Douglas K. Doza, John Y. Liu
  • Patent number: 6395084
    Abstract: Magnesium oxychloride and magnesium oxysulfate materials and methods of making the same are disclosed. The materials are cured reaction products of a magnesium oxide, and an aqueous magnesium salt solution. The aqueous salt solution preferably has a specific gravity of about 1.18 to about 1.4. The magnesium oxide has a platelet or flake structure, a bulk density of about 30 lbs/ft3 (about 0.48 g/cm3) to about 70 lbs/ft3 (about 1.12 g/cm3), and a particle density of about 215 lbs/ft3 (about 3.45 g/cm3) or less. The platelet/flake magnesium oxide is prepared, preferably from particles of magnesium oxide ore or brucite ore, using brine-free methods.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: May 28, 2002
    Inventor: James L. Priest
  • Patent number: 6376405
    Abstract: An economical and environment-friendly process for the synthesis of anionic clays with carbonate and/or hydroxide anions as the charge-balancing interlayer species is disclosed. The process involves reacting a slurry including an aluminum source and a magnesium source, the aluminum source including two types of aluminum-containing compounds, preferably aluminum trihydrate and/or thermally treated calcined aluminum trihydrate. There is no necessity to wash or filter the product. It can be spray dried directly to form microspheres or it can be extruded to form shaped bodies. The product can be combined with other ingredients in the manufacture of catalysts, absorbents, pharmaceuticals, cosmetics, detergents, and other commodity products.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: April 23, 2002
    Assignee: Akzo Nobel N.V.
    Inventors: Dennis Stamires, Michael F. Brady, William Jones, Fathi Kooli
  • Publication number: 20020025468
    Abstract: A solid electrolyte material contains an A site-deficient complex oxide represented by a chemical formula A1-&agr;BO3-&dgr;, in which a B site contains at least Ga. This solid electrolyte material has stability, high oxide-ion conductivity at low temperature and high toughness. A method of manufacturing the solid electrolyte material, comprises: mixing oxide materials of respective constituent elements; baking temporarily the mixed materials at 1100 to 1200° C. for 2 to 10 hours; grinding the temporarily baked materials to powder; molding the powder; and sintering the molded powder. A solid oxide fuel cell, has: the solid electrolyte material; a cathode electrode formed on one surface of the solid electrolyte material; and an anode electrode formed on the other surface of the solid electrolyte material. The solid oxide fuel cell has a stable and long operation at low temperature.
    Type: Application
    Filed: August 28, 2001
    Publication date: February 28, 2002
    Applicant: Nissan Motor Co., Ltd.
    Inventors: Tatsuo Sugiyama, Kazuo Matsuo, Fumio Munakata, Yoshio Akimune
  • Patent number: 6313056
    Abstract: An essentially non-slumping sprayable refractory castable composition that is applied without forms is disclosed comprising (a) a tempered, pumpable first component comprising (i) one hundred weight percent of a refractory composition comprising from about 60 to 90 weight percent of a refractory aggregate, from about 2 to 25 weight percent of an ultrafine refractory material having an average particle diameter size less than or equal to about 3 microns, from about 0.5 to 15 weight percent of a binder, and from about 0.05 to 2.
    Type: Grant
    Filed: August 20, 1998
    Date of Patent: November 6, 2001
    Assignee: Harbison-Walker Refractories Company
    Inventors: Xiangmin Li, Robert M. Cullen
  • Patent number: 6294244
    Abstract: A wiring board of the present invention is equipped with an insulating board formed of a sintered product of silicon nitride containing a silicon nitride crystal phase, and a metal circuit formed on said insulating board, wherein said sintered product of silicon nitride contains a rare earth element (RE) and magnesium in a total amount of from 4 to 30 mol % calculated as oxides and at a molar ratio (RE2O3/MgO) calculated as oxides of from 0.1 to 15, and has a relative density of not smaller than 90% and a heat conductivity of not smaller than 50 W/m·K. The wiring board is equipped with the insulating board having very excellent heat-radiating property and a large strength, and is very useful as a wiring board for, for example, power modules.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: September 25, 2001
    Assignee: Kyocera Corporation
    Inventors: Toshihiro Iwaida, Teruhisa Makino, Masanobu Ishida, Tomohide Hasegawa, Hirosi Okayama
  • Patent number: 6277353
    Abstract: A process for preparing an alkaline earth metal hydroxide which comprises reacting particulate alkaline earth metal oxide having a particle size in the range from about 100 &mgr;m to about 10,000 &mgr;m with a sufficient quantity of water for a sufficient time and at a sufficient temperature to carry out the reaction effectively thereby the alkaline earth metal hydroxide is prepared.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: August 21, 2001
    Inventors: David Richard Gard, Brian David Jurcak
  • Patent number: 6254657
    Abstract: Disclosed is a molding method for powder particles, which is excellent in molding performance, and which makes it possible to obtain a preliminary molded product excellent in strength by enhancing mutual bonding between particles in the preliminary molded product. A molding apparatus for powder particles includes an outer frame die having a mold space with a lower punch and an upper punch to be slidably fitted thereto. Slight clearances exist between the outer frame die and the lower and upper punches. A mixture is prepared by mixing a powdery raw material with a liquid additive to cause an exothermic reaction therewith.
    Type: Grant
    Filed: August 17, 1999
    Date of Patent: July 3, 2001
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventor: Mitsuo Kuwabara
  • Patent number: 6227127
    Abstract: A sintered material includes a polycrystalline substance of MgAl2O4 and/or Al2O3; and 3 to 90 weight percent of Cr2O3 and/or CeO2. Furnace material, furnace wall block, high temperature protection tube, and high temperature protecting member are made of such sintered material, and have higher heat resistance and corrosion resistance.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: May 8, 2001
    Assignee: Kyocera Corporation
    Inventors: Shinichi Yamaguchi, Yasuhiro Tanaka
  • Patent number: 6218335
    Abstract: A porous spinel type oxide shows a large surface area and a uniform micro-porous structure. The oxide is expressed by general formula MO—Al2O3 and shows a surface area per unit weight of not less than 80 m2/g. Such a porous spinel type compound oxide is obtained by impregnating a specific &ggr;-alumina carrier with a solution of a compound of metal element M capable of taking a valence of 2, drying the impregnated carrier and calcining it at a temperature of 600° C. or higher. The specific &ggr;-alumina carrier shows a surface area per unit weight of not less than 150 m2/g, a micro-pore volume per unit weight of not less than 0.55 cm3/g and an average micro-pore diameter between 90 and 200 angstroms. The micro-pores with a diameter between 90 and 200 angstroms occupy not less than 60% of the total micro-pore volume of the carrier.
    Type: Grant
    Filed: July 23, 1999
    Date of Patent: April 17, 2001
    Assignee: Chiyoda Corporation
    Inventors: Yoshimi Okada, Kenichi Imagawa, Susumu Yamamoto
  • Patent number: 6204214
    Abstract: A pumpable ceramic composition is provided comprising an inorganic oxide, potassium phosphate, and an oxide coating material. Also provided is a method for preparing pumpable ceramic-based waste forms comprising selecting inorganic oxides based on solubility, surface area and morphology criteria; mixing the selected oxides with phosphate solution and waste to form a first mixture; combining an additive to the first mixture to create a second mixture; adding water to the second mixture to create a reactive mixture; homogenizing the reactive mixture; and allowing the reactive mixture to cure.
    Type: Grant
    Filed: July 29, 1998
    Date of Patent: March 20, 2001
    Assignee: University of Chicago
    Inventors: Dileep Singh, Arun S. Wagh, Lamar Perry, Seung-Young Jeong
  • Patent number: 6194083
    Abstract: A ceramic composite material comprises a ceramic material constituting a matrix, and dispersion particles disposed in the matrix in a dispersing manner. A specific shape of a ceramic composite material is, for instance, a sinter or a thermally sprayed layer. The dispersion particles are consisting of a composite oxide including at least one kind of a first metallic element selected from alkaline earth metals such as Mg and Ca, and at least one kind of a second metallic element selected from W, Ti, Ta, Mo, Nb, V, B, Te, Ge and Si, for instance, are composite oxide particles precipitated by reacting a compound containing a first metallic element and a compound including a second metallic element through heat treatment. The precipitated particles consisting of such a composite oxide can be dispersed as planar particles or acicular particles in the ceramic layer to which, for instance, thermal spraying is applied.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: February 27, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuhiro Yasuda, Seiichi Suenaga, Kunihiko Wada, Hiroki Inagaki, Yasuhiro Goto
  • Patent number: 6171991
    Abstract: This patent describes an economical and environment-friendly continuous process for the synthesis of anionic clay-containing compositions. It involves reacting a slurry comprising aluminium trihydrate and/or its calcined form, with a magnesium source. There is no necessity to wash or filter the product. It can be spray dried directly to form microspheres or can be extruded to form shaped bodies. The product can be combined with other ingredients in the manufacture of catalysts, absorbents, pharmaceuticals, cosmetics, detergents, and other commodity products.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: January 9, 2001
    Assignee: Akzo Nobel NV
    Inventors: Dennis Stamires, Michael F. Brady, William Jones, Fathi Kooli
  • Patent number: 6137672
    Abstract: The process for the production of a laminated electronic part containing a major component as represented by general formula:X(Mg.sub.a Zn.sub.(1-a)).sub.x SiO.sub.x+2 --YAl.sub.2 O.sub.3 --ZSrTiO.sub.3(where symbol a is defined by: 0.1.ltoreq.a.ltoreq.0.8; and symbol x is defined by: .ltoreq.x.ltoreq.1.5);and an additive component comprised of a compound containing one or more elements selected from Nb, Ta and W;wherein a mole percent ratio of magnesium zinc silicate, (Mg.sub.a Zn.sub.(1-a)).sub.x SiO.sub.x+2, (X), to alumina, Al.sub.2 O.sub.3, (Y), and strontium titanate, SrTiO.sub.3, (Z), each of which constitutes said major component, is set to be located in a region enclosed by a polygon having apexes at points A, B, C and D, as defined below, in a three-component composition map:______________________________________ A (94.9, 0.1, 5.0) B (85.0, 10.0, 5.0) C (65.0, 10.0, 25.0) D (65.0, 0.1, 34.9); ______________________________________and the additive component is contained at a rate of 0.01 to 0.
    Type: Grant
    Filed: February 5, 1998
    Date of Patent: October 24, 2000
    Assignee: Taiyo Yuden Co., Ltd.
    Inventors: Youichi Mizuno, Yasuyuki Inomata, Toshikazu Toba, Hirokazu Chazono
  • Patent number: 6113802
    Abstract: An insulation material which is substantially free of fibers and which has a density of less than about 2.5 g/cc and a thermal conductivity of less than about 5 W/Km is formed from a composition comprising at least about 2%, by weight, carbon. The insulation material is resistant to thermal shock and is easily machined.
    Type: Grant
    Filed: March 19, 1998
    Date of Patent: September 5, 2000
    Assignee: Micropyretics Heaters International, Inc.
    Inventor: Srinivas Penumella
  • Patent number: 6103651
    Abstract: This invention is directed to ceramic metal composite useful as a refractory and having improved abrasion, corrosion, and oxidation resistance. The ceramic metal composite of the present invention is comprised of ceramic refractory aggregate, metal particulate, and a nonaqueous binder wherein the ceramic refractory aggregate, metal particulate, and binder residuals react to form a three-dimensional ceramic-metal matrix. The ceramic-metal matrix is further stabilized by bonds between the metal particulate, reaction products of the metal particulate, and the ceramic refractory aggregate.
    Type: Grant
    Filed: February 7, 1996
    Date of Patent: August 15, 2000
    Assignee: North American Refractories Company
    Inventor: Timothy A. Leitzel
  • Patent number: 6039865
    Abstract: Phosphates can be removed from a hydrocarbon stream by contacting said stream with a ceramic formed of a basic material which is insoluble in the hydrocarbon stream. A ceramic as used in this patent document is a solid solution formed by calcination of a compound. The removal of the organic acid is accomplished at temperatures ranging from 20.degree. C. to 400.degree. C., a preferred temperature is between 200.degree. C. and 370.degree. C. A hydrocarbon stream consists of C.sub.5 + hydrocarbons. The basic material can be made up of one or more alkaline earth oxides, alkaline earth compounds, alkaline metal compounds, group IIIA element compounds, group IVA element compounds, group VIA element compounds. Preferred alkaline earth oxides are sodium, magnesium, potassium, calcium, aluminum and silicon. The support for the basic material can be made from any inorganic oxide.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: March 21, 2000
    Assignee: Trisol Inc.
    Inventor: Shaun T. E. Mesher
  • Patent number: 6017839
    Abstract: The present invention is ceramic article of stabilized zirconia wherein the stabilized zirconia has a molar ratio of rare earth oxide:zirconia of from 1:99 to 15:85, at a weight percent of from about 97 to 75. The ceramic article includes smectite clay from about 3 to 25 weight percent wherein the article is a mass of sintered particles having a continuous tetragonal phase having dispersed therein monoclinic phase particles having size of less than 100 nm.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: January 25, 2000
    Assignee: Eastman Kodak Company
    Inventors: Debasis Majumdar, Dilip K. Chatterjee, Syamal K. Ghosh
  • Patent number: 5981415
    Abstract: A ceramic composite material consisting of two or more crystal phases of different components, each crystal phase having a non-regular shape, said crystal phases having three dimensional continuous structures intertwined with each other, at least one crystal phase thereof being a single crystal. Further, by removing at least one crystal phase from this ceramic composite material, there is provided a porous ceramic material consisting of at least one crystal phase and pores, said crystal phase and pores having non-regular shapes and being three dimensionally continuous and intertwined with each other.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: November 9, 1999
    Assignee: UBE Industries, Ltd.
    Inventors: Yoshiharu Waku, Narihito Nakagawa, Kazutoshi Shimizu, Hideki Ohtsubo, Takumi Wakamoto, Yasuhiko Kohtoku
  • Patent number: 5942453
    Abstract: A powdered mixture of chemicals for forming a refractory composition, including a filler consisting of refractory particles, metal particles and metal peroxide containing particles, wherein the metal peroxide containing particles have a calcium peroxide content of at most 75 wt %, a magnesium peroxide content of at most 30 wt %, a barium peroxide content of at most 92 wt %, and/or a strontium peroxide content of at most 90 wt %. A refractory composition prepared from said mixture, a method for forming said composition and a method for using same are also disclosed.
    Type: Grant
    Filed: September 10, 1996
    Date of Patent: August 24, 1999
    Assignee: FIB-Services
    Inventor: Oswaldo Di Loreto
  • Patent number: 5885520
    Abstract: A nozzle or tube which is useful for pouring molten metal, especially aluminum killed molten steel. The nozzle is formed from a blend of doloma and graphite which is bonded together in a carbonized matrix. Nozzles or tubes made in accordance with this invention have enhanced thermal shock resistance. Furthermore, the nozzles or tubes of this invention resist the formation of aluminum oxide therein when they are used for pouring molten aluminum killed steel. Consequently, these tubes or nozzles can be used in a continuous casting process for a long period of time without having to periodically stop the procedure and change the tubes as they become blocked with aluminum oxide. As a result of the thermal shock resistance, the usual preheating step prior to contacting the nozzle with the molten metal is greatly reduced.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: March 23, 1999
    Assignee: Baker Refractories
    Inventor: Donald B. Hoover
  • Patent number: 5880046
    Abstract: This moldable refractory composition is intended to be used in the production of cast refractory pieces resistant to molten metals, especially molten aluminum. It comprises 8 to 25% by weight of an aqueous phosphoric acid solution having a concentration of phosphoric acid ranging from 40 to 85% by weight, with up to 50% of the primary acidic function of the acid phosphoric acid neutralized by reaction with vermiculite. It also comprises from 75 to 92% by weight of a mixture containing wollastonite and an aqueous suspension containing from 20 to 40% by weight of colloidal silica. The weight ratio of the aqueous suspension to the wollastonite within the mixture ranges from 0.5 to 1.2. The composition according to the invention is particularly interesting in that it can be unmolded within a very short period of time that is less than 2 hours and can be as small as 10 minutes.
    Type: Grant
    Filed: January 23, 1998
    Date of Patent: March 9, 1999
    Assignee: Cerminco Inc.
    Inventors: Pierre Delvaux, Luc Desrosiers, Marcel Gouin, Louis Campagna
  • Patent number: 5858261
    Abstract: The invention is related to a continuous casting nozzle for casting of aluminum killed steel without clogging of the bore of the nozzle. The surface layer of the bore of the continuous casting nozzle contacting with the molten steel is formed of a refractory comprising graphite from 10 to 35 wt % and roseki as the remaining part of the graphite, and the main component of the roseki is pyrophyllite (Al.sub.2 O.sub.3.4SiO.sub.2.H.sub.2 O) as mineral component. Further, silicon carbide from 1 to 10 wt % is contained in the refractory.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: January 12, 1999
    Assignee: Akechi Ceramics Kabushiki Kaisha
    Inventors: Toshiyuki Muroi, Kazumi Oguri
  • Patent number: 5854157
    Abstract: An object of the present invention is to provide a novel ceramic composite that has not only excellent dynamic characteristics, but also good electromagnetic characteristics, typified by dielectric characteristics, and the present invention relates to a ceramic composite, characterized in that an oxide having a perovskite structure which includes as raw materials lead and/or an alkaline earth metal is dispersed in a ceramic matrix, and in the above-mentioned ceramic composite, preferably the ceramic matrix is MgO, MgAl.sub.2 O.sub.4, or ZrO.sub.2, and also, preferably in the above-mentioned ceramic composite, the perovskite structure oxide particles are covered with MgO, MgAl.sub.2 O.sub.4, or ZrO.sub.2, and the ceramic matrix is Al.sub.2 O.sub.3.
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: December 29, 1998
    Assignees: Agency of Industrial Science and Technology, Fine Ceramics Research Association
    Inventors: Hae Jin Hwang, Masaki Yasuoka, Mutsuo Sando, Toru Nagai, Koichi Niihara
  • Patent number: 5830815
    Abstract: A method for regulating the reaction temperature of a ceramic formulation process is provided comprising supplying a solution containing a monovalent alkali metal; mixing said solution with an oxide powder to create a binder; contacting said binder with bulk material to form a slurry; and allowing the slurry to cure. A highly crystalline waste form is also provided consisting of a binder containing potassium and waste substrate encapsulated by the binder.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: November 3, 1998
    Assignee: The University of Chicago
    Inventors: Arun S. Wagh, Dileep Singh, Seung-Young Jeong
  • Patent number: 5786978
    Abstract: The dielectric ceramic composition for use with a laminated capacitor to be used in a high frequency region improves in costs of manufacturing by lowering the temperature of calcination as relatively high as from ca. 1,200.degree. C. to 1,500.degree. C. required for conventional ones and by reducing the expensive costs of electricity required otherwise by the manufacture of conventional ones. The dielectric ceramic composition contains a magnesium silicate-zinc component, an alumina component and a strontium titanate component, as represented by formula:Z(Mg.sub.a Zn.sub.(1-a)).sub.x SiO.sub.x+2 --YAl.sub.2 O.sub.3 --ZSrTiO.sub.3wherein a is equal to or larger than 0.1 and equal to or smaller than 0.8; and x is equal to or larger than 0.67 and equal to or smaller than 1.5; and wherein a molar ratio (%) of the magnesium silicate-zinc component, as represented by (Mg.sub.a Zn.sub.(1-a)).sub.x SiO.sub.x+2, to the alumina component, as represented by Al.sub.2 O.sub.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: July 28, 1998
    Assignee: Taiyo Yuden Co., Ltd.
    Inventor: Youichi Mizuno
  • Patent number: 5767029
    Abstract: Metal-ceramic composite materials which combine advantageous properties of ceramic and metal and have the composition (Mg.sub.1-x Cu.sub.x)O+Ag.sub.y, where 0.03.ltoreq.x.ltoreq.0.25 and 0.001.ltoreq.y.ltoreq.0.5, can be produced in a one-stage process. In this process, sintering is carried out in air at a sintering temperature in the temperature range of 980.degree. C.-1100.degree. C. for a sintering time in the range of 1.5-2.5 hours. The rate of temperature rise from room temperature to the sintering temperature is in the range of 8-50 K/min. When 0.01.ltoreq.y.ltoreq.0.1, such composite materials are suitable as materials having high toughness for low-friction, self-lubricating sliding bearings, in particular of ceramic. When 0.1.ltoreq.y.ltoreq.0.2, they are suitable as electrical contact materials in fuel cells and for abrasion-resistant sliding contacts. When 0.15.ltoreq.y.ltoreq.0.5, the composite materials have a high conductivity.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: June 16, 1998
    Assignee: ABB Research Ltd.
    Inventor: Claus Schuler
  • Patent number: 5747400
    Abstract: A colored refractory material for lining an instrument/apparatus used at a high temperature is formed by mixing a powder of a raw material containing ceramics with a coloring agent and kneading with a liquid using a binder. The refractory material is put in lining for a portion being in contact with a high temperature molten substance or being exposed to a high temperature atmosphere, and is dried by heating while adjusting a temperature and a heating time on the basis of color change on the surface of the refractory material.
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: May 5, 1998
    Assignee: Nippon Crucible Co., Ltd
    Inventors: Tadao Sasaki, Hideaki Ohashi, Akio Ueda, Norio Honda, Hiroyuki Suzuki
  • Patent number: 5731250
    Abstract: Ceramic bodies comprised mainly of zircon and wollastonite, with zircon being the dominant crystalline phase, show improved resistance to alkaline conditions at elevated temperatures than conventional bodies and excellent thermal stability.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: March 24, 1998
    Assignee: Norton Chemical Process Products Corporation
    Inventors: John S. Reid, Thomas Szymanski
  • Patent number: 5700309
    Abstract: A method of repairing an oxide-based refractory body by projecting a powder mixture against a hot surface of the body and in the presence of oxygen to provide a refractory repair mass includes providing a powder mixture composed of particles of at least one refractory oxide; fuel particles which react in an exothermic manner with the oxygen to form a refractory oxide and which are particles composed of at least one element selected from the group consisting of magnesium, aluminum, silicon, and mixtures thereof; and particles of silicon carbide present in an amount which is effective to provide a reduced porosity of the refractory repair mass and which does not exceed 10% by weight based on the weight of the powder mixture; and projecting the powder mixture against a hot surface of the oxide-based refractory body and in the presence of oxygen. Preferably, the powder mixture contains at least 1%, most preferably from 1 to 5%, by weight of the particles of silicon carbide.
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: December 23, 1997
    Assignee: Glaverbel
    Inventors: Alexandre Zivkovic, Jean-Pierre Meynckens, Bernard Somerhausen
  • Patent number: 5656562
    Abstract: A method for improving the properties of ceramic green bodies is provided. In particular, ceramic green bodies having improved green strength are provided. Incorporating certain acid-containing polymers as binders at a level of at least about 1 to about 15, preferably at least about 3 to about 10 percent by weight based on the weight of ceramic particles improves the green strength of the resulting ceramic green bodies.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: August 12, 1997
    Inventor: Xianliang Wu
  • Patent number: 5629251
    Abstract: A ceramic coating-forming agent of an Mg-M.sup.3+ -O based two-component oxide solid solution capable of forming a ceramic coating excellent in heat resistance, adhesion to a substrate metal, electric insulation and the properties of low thermal expansion, at a low temperature, the agent containing an Mg-M.sup.3+ -O based two-component oxide solid solution of the formula (1),(Mg.sub.1-x M.sup.2+.sub.x).sub.1-y M.sup.3+.sub.y O (1)wherein M.sup.2+ is at least one divalent metal selected from the group consisting of Ca.sup.2+, Mn.sup.2+, Fe.sup.2+, Co.sup.2+, Ni.sup.2+, Cu.sup.2+ and Zn.sup.2+, M.sup.3+ is at least one trivalent metal selected from the group consisting of Al.sup.3+, Mn.sup.3+, Fe.sup.3+, Co.sup.3+, Ni.sup.3+, Ti.sup.3+, Bi.sup.3+ and Cr.sup.3+, x is a number in the range of 0.ltoreq.x<0.5 and y is a number in the range of 0<y<0.5, or an anionic oxide-dispersed Mg-M.sup.3+ -O based two-component oxide solid solution of the formula (2),(Mg.sub.1-x M.sup.2+.sub.x).sub.1-y M.sup.3+.sub.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: May 13, 1997
    Assignee: Kabushiki Kaisha Kaisui Kagaku Kankyujo
    Inventor: Shigeo Miyata
  • Patent number: 5624604
    Abstract: A method for dispersing and reducing the rate of dissolution and/or hydration of colloidal ceramic suspensions is described. The method comprises adding to a ceramic suspension a non-polymeric hydroxylated organic compound. The organic compound has at least one hydroxyl group, preferably at least two hydroxyl groups. The organic compound also includes a functional group selected from the group consisting of a carboxyl, a carboxylate, a sulfonic acid, a sulfonate, a phosphoric acid, a phosphate, an amine, and a quaternary ammonium salt. The ceramic suspension typically comprises a colloidal suspension of a metal oxide, wherein the metal of the metal oxide is an alkali metal, alkaline-earth metal or a rare-earth metal, but preferably is magnesium, calcium or a rare-earth metal. The non-polymeric organic compound is added to the suspension in an amount effective to substantially disperse and reduce the rate of dissolution of the ceramic particles, such as from about 0.01 weight percent to about 5.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: April 29, 1997
    Inventors: Mehrdad Yasrebi, William W. Kemp, David H. Sturgis, Ilhan A. Aksay, Hamazo Nakagawa
  • Patent number: 5609961
    Abstract: The single-layer high temperature coating according to the invention, which is applied in particular on a porous substrate, comprises a high silica glaze gel frit, alumina and an emissivity agent consisting of MoSi.sub.2 or Cr.sub.2 O.sub.3, and has the following composition by weight:gel frit: 45 to 55%;MoSi.sub.2 or Cr.sub.2 O.sub.3 : 25 to 50%;Al.sub.2 O.sub.3 : 5 to 20%.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: March 11, 1997
    Assignees: Aerospatiale Societe Nationale Industrielle VIAM-, All Russian Institut of Aviation Materials
    Inventors: Galina A. Solovjeva, Vladimir M. Tjurin, Stanislav S. Solntsev
  • Patent number: 5607630
    Abstract: A ceramic moulded body containing at least 10 vol. % fine-grained Al.sub.2 O.sub.3, and a process for its production(a) milling aluminium metal in powder form alone or together with Al.sub.2 O.sub.3 or/and if desired further suitable inorganic substances for ceramic formation in a non-aqueous liquid in the presence of oxygen until 10 to 80% of the metallic aluminium powder has reacted to form one or several aluminium oxidation precursors from the group amorphous Al.sub.2 O.sub.3, .gamma.-Al.sub.2 O.sub.3 and aluminium-organic compounds and the powder has a maximum oxidation rate between 510.degree. and 610.degree. C. according to differential thermoanalytical measurement;(b) molding the powder of step (a) into a green body;(c) slowly heating the green body in an atmosphere containing oxygen to a temperature which is below the melting temperature of aluminium until at least 50% of the metallic aluminium powder remaining after the milling has reacted to Al.sub.2 O.sub.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: March 4, 1997
    Inventor: Nils Claussen
  • Patent number: 5607887
    Abstract: The present invention provides a method for preparing a ceramic mixed-oxide of at least two metals including mixing an alloy with a ceramic oxide. The alloy including a metal selected from the group consisting of aluminum, calcium, lithium, magnesium, silicon, titanium, yttrium, and zirconium. The alloy also includes an element that is to be present in the ceramic mixed-oxide. The element is different from the metal and is selected from the group consisting of aluminum, calcium, lithium, magnesium, a combination of magnesium and silicon, silicon, titanium, yttrium, and zirconium. The ceramic oxide includes a metal that is to be present in the ceramic mixed oxide. The alloy and ceramic oxide are co-milled. The mixed and co-milled alloy and ceramic oxide are reaction-sintered, thereby oxidizing the metal and element of the alloy to produce the ceramic mixed-oxide.
    Type: Grant
    Filed: February 15, 1995
    Date of Patent: March 4, 1997
    Assignee: Volvo Aero Aktiebolag
    Inventors: Lars Pejryd, Robert Lundberg, Jesper Brandt
  • Patent number: 5602063
    Abstract: The present invention discloses a low density basic refractory lining material with improved resistance to corrosion by molten slag and metal that is especially adapted for use as a disposable liner in molten metal containing vessels. This material incorporates hollow ceramic microspheres of alumina, silica or mixtures thereof, having diameters of between about 5 and 500 microns as a density reducing material. This material may also include a stiffening agent, a set retarding agent, a foaming agent to further reduce the density, a plasticizer, and a low temperature binder. The addition of the ceramic microspheres has been found to provide reduced open porosity, improving resistance to corrosion. Also, the invention relates to methods for applying the disposable lining and vessels which include the lining applied thereon.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: February 11, 1997
    Assignee: Minteq International, Inc.
    Inventors: Julie A. Dody, Charles R. Rumpeltin, Jr.